Water in oil...but where from?

[bob6600]

A follow on from my head gasket thread, I am stumped as to where water is getting into the oil. 'Mayo' under the cap but no temperature rise. Evidence of water up the dipstick too. The oil cooler seems ok too so ruled that out (ATF seems clean enough too).

So, I decided that it was time to tackle the dreaded head gasket. After getting everything off, I was pleased and gutted that the head gasket and head both look fine.

So, where else can water get into the oil on a W210 E320 CDI OM613 engine? I am assuming the water would have to get in via the cylinder head and that the crankcase has nothing to do with it.

I don't want to replace the head unless I need to but likewise I don't want to put it back together and still be losing water anywhere.

Any ideas? A few pics

 

[markjay]

Mayo on the filler cap is normal.

Mayo on the dipstick is not.

(On a general note, there are various ways of checking for blown head gasket, including gas analyser in the coolant expansion bottle, but now the engine is apart that is no longer relevant)

If you can't see any obvious signs of blow-through on the old head gasket, then check if your car is equipped with a heat exchanger - essentially a small radiator that runs engine oil and is immersed in coolant. Not sure if your engine has that though.

 

[kianok]

A crack in the head somewhere?

 

[grober]

The most likely candidate is indeed the cylinder head. It may have warped slightly or developed a crack/corroion somewhere. Only way to check properly is on an engineering bench [ ultraflat surface] or by pressure testing. A good engine reconditioning facility should be able to do this for you at reasonable cost. [ stripping the engine yourself will keep the cost down]They may be able to weld repair any defect before planing the head completely flat again. To do this well is a bit of a black art so choose your engine specialist carefully.
The other suspect would be the gasket between the small finned heat exchanger and the oil galleries that form part of the oil filter housing or the heat exchanger itself. Lots of stuff on the net about this on the OM613 engine.
OIL FILTER AND OIL COOLER MERCEDES E-KLASSE [Car] [CHASSIS] (EUROPA)

 

[grober]

The gasket between the two is fairly elaborate and you can see how a leak there would lead to the oil and water getting mixed together.
Best illustrated by a couple of pictures on a different engine . I believe they may have changed the seal eleastomer material also
Mercedes-Benz W204 Oil Cooler and Seal Replacement - (2008-2014) C250, C300, C350 | Pelican Parts DIY Maintenance Article

and

 

[jaymanek]

Bob you definitely cannot put it back together without a pressure test and skim of the head.

There are a few local places but we use IB engineering on heath end road.

Have you ruled out oil cooler? I recall you talking about it some time ago.

 

[Joesoap17]

That head looks to me as if it could be passing at a couple of points on first picture, where the sealing ring around each cylinder is incomplete?
I would get the head checked for flatness and skimmed before putting it back together.

 

[bob6600]

Thanks for the replies gents.

Bob you definitely cannot put it back together without a pressure test and skim of the head.

There are a few local places but we use IB engineering on heath end road.

Have you ruled out oil cooler? I recall you talking about it some time ago.

I have taken the oil cooler off and the water and ATF seem fine. The Oil was contaminated with water but I can't say where from. I will give IB a call, thanks Jay. I also have two snapped glow plugs and although they have never bothered me, now is the time to get them out as the head is off. I could do it myself but maybe best to let an expert do it. Any recommendations?

The gasket between the two is fairly elaborate and you can see how a leak there would lead to the oil and water getting mixed together.
Best illustrated by a couple of pictures on a different engine . I believe they may have changed the seal eleastomer material also
Mercedes-Benz W204 Oil Cooler and Seal Replacement - (2008-2014) C250, C300, C350 | Pelican Parts DIY Maintenance Article

and

Thanks grober. The gasket is indeed flimsy and much thinner than the W204 pictured!

 

[bob6600]

A crack in the head somewhere?

Can't see one but it may have one in the internal galleries so will have to get it pressure tested.

Mayo on the filler cap is normal.

Mayo on the dipstick is not.

(On a general note, there are various ways of checking for blown head gasket, including gas analyser in the coolant expansion bottle, but now the engine is apart that is no longer relevant)

If you can't see any obvious signs of blow-through on the old head gasket, then check if your car is equipped with a heat exchanger - essentially a small radiator that runs engine oil and is immersed in coolant. Not sure if your engine has that though.

This would be the oil cooler which I think can be eliminated but it was late yesterday so will inspect properly today/tomorrow (Grand Prix is on soon )

 

[markjay]

...I have taken the oil cooler off and the water and ATF seem fine....

To clarify, we are talking about the engine-oil/coolant heat exchanger located in or on the engine block, not the ATF/coolant heat exchanger located in the radiator.

 

[bob6600]

To clarify, we are talking about the engine-oil/coolant heat exchanger located in or on the engine block, not the ATF/coolant heat exchanger located in the radiator.

Yes mate, the one as per grober's first post, item no.35

 

[bob6600]

Bob you definitely cannot put it back together without a pressure test and skim of the head.

There are a few local places but we use IB engineering on heath end road.

Have you ruled out oil cooler? I recall you talking about it some time ago.

Head went off to IB Engineering this afternoon. Such a helpful guy with plenty of knowledge - I can see why you go there Jay! Love these 'old school' places, I could have stayed there and chatted for ages! He suspects some gasket failure near one or possibly two cylinders but will pressure test to confirm if the head is ok. Prices are very reasonable too. Thanks again @Mercland

 

[clk320x]

Head went off to IB Engineering this afternoon. Such a helpful guy with plenty of knowledge - I can see why you go there Jay! Love these 'old school' places, I could have stayed there and chatted for ages! He suspects some gasket failure near one or possibly two cylinders but will pressure test to confirm if the head is ok. Prices are very reasonable too. Thanks again @Mercland

If you got some free time now I’ll bring round my e320?

Few jobs to do

 

[jaymanek]

Head went off to IB Engineering this afternoon. Such a helpful guy with plenty of knowledge - I can see why you go there Jay! Love these 'old school' places, I could have stayed there and chatted for ages! He suspects some gasket failure near one or possibly two cylinders but will pressure test to confirm if the head is ok. Prices are very reasonable too. Thanks again @Mercland

Mark is a fantastic person to know. He was too busy to do my 500E engine at the time, but he helped me loads when the "other place" messed up. Would never go anywhere else.
He is never short of work and I cant recall ever having a problem with anything he has done.

 

[bob6600]

Mark is a fantastic person to know. He was too busy to do my 500E engine at the time, but he helped me loads when the "other place" messed up. Would never go anywhere else.
He is never short of work and I cant recall ever having a problem with anything he has done.

He is a star. Stayed late and rang me around 18.30 to say it has passed the pressure test and was only very slightly bowed but nothing a klght skim won't fix. Tomorrow should be valves out and cleaned, second glow plug drilled and then then skimmed. Should be back together if the valve stem seals turn up otherwise will be Thursday. Meanwhile, I can clean all the parts and bolts ready to go back on and de-grease the engine bay a bit.

 

[bob6600]

Head was back yesterday (24hr turnaround!) and I couldn't help myself but put it back on the car even though the sun had gone down.

 

[clk320x]

Head was back yesterday (24hr turnaround!) and I couldn't help myself but put it back on the car even though the sun had gone down.

Sounds good Bob, hopefully this has resolved the problem

 

[markjay]

Head was back yesterday (24hr turnaround!) and I couldn't help myself but put it back on the car even though the sun had gone down.

.......and??

 

[bob6600]

.......and??

Head is on, camshafts, HP pump and some other minor bits. I'e rotated the engine and timing seems ok. Will be a few more days yet as I'm awaiting some parts to finish the job plus in my condition I can only do a bit at a time. I am also cleaning everything before it goes back on (even the bolts lol) so a lot to do. The oil cooler was jammed with gunk so had to clean that out. Will post pics later if I get a chance.

 

[Joesoap17]

Good stuff,
a jobs only worth doing if you are going to do it right, so clean away it probably needs it!!